Guide shell for rock drills



Nov. 27, 1934. J. c. CURTIS 1,981,992

GUIDE SHELL FOR'ROCK DRILLS Filed June 13, 1932 JOHN c'. ewe 775INVENTOR ATTORNEY- Patented Nov. 27, 1934 units!) srArss GUIDE SHELL FDRROCK DRILLS John 0. Curtis, Cleveland, Ohio, assignor to The ClevelandRoch Drill Company, Cleveland, Ohio,

a corporation of Ohio Application June 13, 1932, Serial No. 616,777

3 Claims.

This invention relates broadly to rock drills but more particularly toguide shell for rock drills of the drifter type.

Generally the guide shells for rock drills are provided with a pair oflongitudinally disposed guide ways within which the guide bars of therock drill cylinder are free to slide back and forth. It has been foundthat the engaging surfaces of such guide ways and guide bars are liableto wear and to affect the accuracy with which the rock drill will slidein the shell. To remedy this deleterious condition, it was necessary toreplace the complete guide shell and often the cylinder of the rockdrill, thus increasing the cost of operation.

One of the objects of this invention is to construct a guide shell withdetachable guide bars upon which the rock drill may slide, permittingthereby the renewal of the Worn guide bars to restore the assembly toits original condition.

Another object of this invention is to provide a guide shell for rockdrills manufactured out of relatively fiat stock bent to a desired shapewith enlarged guide bars of sufficient cross section to afford adequaterigidity, and enable the guide shell to withstand the severe strains towhich mountings of this type are subjected, thus reducing the cost ofmanufacture and also maintaining the weight of the guide shell to aminimum.

Other objects more or less ancillary to the foregoing and the manner inwhich the various objects are attained reside in the specificconstruction and aggroupment of the elements peculiar to thisconstruction, as will become apparent from a more complete examinationof this specification, in the claims of which there are assembledcertain specific combinations indicative of the scope and spirit of theinvention.

In the drawing:

Fig. l is a cross sectional view of the assembly illustrating theinvention.

Fig. 2 is a cross sectional view of the guide shell assembly taken in aplane indicated by line 22 in Fig. 3.

Fig. 3 is an end View of the guide shell assembly as seen by looking inthe direction pointed out by the arrows 3-3 in Fig. 2.

Fig. 4 is a perspective end view of the guide shell and the guiding barsready to be assembled.

Referring now to the drawing, represents the body of a guide shellmanufactured of relatively thin flat stock bent substantially to a Ushape. The outer ends of the side walls thereof are bent inwardly toform two gibs 11 in parallel alignment with each other and extendingsubstantially the full length of the guide shell. Circumventing each ofthe gibs 11, there is a guide bar 12 provided with a slot 13 extendingthe full length of the bars for engagement over thegibs 11. For thepurpose of securing the guide bars 12 upon the gibs 11, one end of thesegibs is provided with a cut away portion or notch 14 formed on the external side of the-gibs. Toward the other end, the gibs 11 are providedwith an aperture 15 vertically disposed therethrough. One end of theguide bars 12 is provided with a tongue 16 pro jecting from the upper'wall thereof and of a width substantially equal to the width of thenotches 14. Toward the other end, the upper and lower wall of the guidebars 12 are provided with vertically disposed apertures 17. Secured tothe lower wall of the shell 10, there is a cone 18 by which the completeassembly may be afiixed to any suitable supporting device.

In assembling the guide shell, the guide bars 12 are positioned over thegibs 11 in such a manner as to afford the registration of the apertures17 with the apertures 15. Through these apertures there is introduced abolt 19 capable of screw tight engagement with a nut 20 for clamping theparts together. Subsequently the tongues 16 are bent downwardly withinthe notches 14 as illustrated in Fig. 3, thus rigidly securing the guidebars 12 upon the gibs 11. The bolts 19 are primarily intended to preventthe longitudinal movement of the guide bars, while the tongues 16 withinthe notches 14 are intended to limit the lateral movement of the guidebars with respect to the guide shell.

The rock drill comprises a cylinder 21 having provided within the lowerportion thereof two longitudinally disposed guide ways 22 affordingwearing surfaces 23 and 24 capable of slidable engagement upon the guidebars 12.

With this construction, it will be seen that the guide bars 12 mayreadily be renewed by removing the bolts 19, and sliding the tongues 16and guide bars 12 out of their respective engagement with the notches 14and gibs 11. The guide shell body is never submitted to wear, thus theassembly may remain in use by replacing the worn guide bars by oversizeguide bars to compensate for the wear of the bearing surfaces 23 and 24of the guide ways 22. By bending the tongues 16 downwardly into thenotches 14, the cylinder 20 is free to pass over that end of the guidebars without any interference. The bolts 18 are positioned in such amanner as to not interfere with the rearward travel of the cylinder.

This travel is limited by the reed screw bushing generally locatedwithin that end of the guide shell and ahead of the bolts 18.

Although the foregoing description is necessarily of a detailedcharacter, in order to completely set forth the invention, it is to beunderstood that the specific terminology is not intended to berestrictive or confining and it is to be further understood that variousrearrangements of parts and modification of structural detail may beresorted to without departing from the scope or spirit of the inventionas herein claimed.

I claim:

1. A support for rock drill comprising an elongated shell formed withside walls having guide bars receiving walls extending therefrom inparallelism, guide bars detachably secured to said.

guide receiving walls, guideways within said rock drill adapted toreceive said guide bars for slidable movement thereon, notches withinone end of said shell adapted to receive a tongue depending from one endof said guide bars for preventing the lateral movement of the latterwith respect to theformer, and detachable means comprising a bolt and anut for securing the other end of said guide bars to'said shell, theremoval of said last mentioned means permitting the removal of saidguide bars from said shell irrespective of the engagement of saidtongues with said notches,

2. A support for rock drill comprising an elongated shell formed withside walls having guide bars receiving walls extending therefrom inparallelism, guide bars detachably secured to said guide receivingwalls, guideways within said rock drill adapted to receive said guidebars for slidable movement thereon, means formed on said shell and saidguide bars engageable with each other for locking one end of the latteragainst relative lateral movement with the former, and removable meansfor securing the other end of said guide bars to said shell, the removalof said last mentioned means permitting the removal of said guide barsfrom said shell irrespective of said first mentioned means.

3. A support for rock drill comprising an elongated shell formed withside walls having guide bars receiving walls extending therefrom inparallelism, guide bars detachably secured to said guide receivingwalls, guideways within said rock drill adapted to receive said guidebars for slidable movement thereon, means formed on said shell and saidguide bars engageable with each other for locking one end of the latteragainst relative lateral movement with the former, said means beinglocated within the path of the slidable movement of said rock drill onsaid guide bars and permitting said movement, and removable meanslocated out of said path for securing the other end of said guide barsto said shell, the removal of said last mentioned means permitting theremoval of said guide bars from said shell irrespective of said firstmentioned means.

' 'JOHN C. CURTIS.

